A portable fan with good user reviews. This one is for work spaces. Some say, too ugly for home use. It moves a massive amount of air and is almost whisper quiet, because it has a rotating drum instead of airplane propellor type blades. Given what it does on speed #1, I see no need to turn it up. I don't know if it is more efficient than conventional fans, but I'm confident that it is more effective. After the sun goes down, it draws a blast of cooler night air through an open window. I have no idea what it will do to my electric bill, but it is cheaper than A/C, which has an energy-sucking compressor motor. The image above is of a Lasko Pro Performance 4900 $75, which is what I bought from Amazon. Lasko makes other models, some smaller and less costly. Stanley offers one of similar appearance which is made by Lasko. I hope that this is useful information given what promises to be a hot summer.